detention centre

Meaning: any place in which people are imprisoned without charge or a trial

For example:

Our detention centres are very secure and our detainees never escape.

Many of the men, women and children in this detention centre have been here for years.

Note:In recent years, "detention centre" has often been used as a euphemism for an immigration jail or prison camp in which refugees or asylum seekers who've entered a country without permission are held. Most have escaped from war, persecution or poverty and many are held for long periods without charge in what's called "administrative detention". Many lawyers and human rights experts have stated that holding people in detention centres without charge is a human rights abuse under international law.